The present invention relates to a device for the selection of large loose reams.
In the case of large reams, that is to say, the reams used for sketches, drawings, printed copies, etc., a significant problem is ream selection in the machines designed to package them into separate packs.
The sheets to be fed to the packaging machines, arriving from the cutting machine which produces them, are placed on a pallet in the form of a pack; the pallet is then positioned on a lift which gradually raises it automatically as an operator above selects and removes a pack of sheets destined to form a ream, so that the sheets are always piled to the same height.
The use of an instrument similar to a gauge is normally envisaged for the selection of the ream from the pack of sheets, the fixed measuring arm being an element similar to a stop, and the movable arm being a blade which may be inserted between one sheet and the next. The operator determines the thickness of the ream to be obtained in accordance with the number of sheets of which it must consist and their thickness, then rests the gauge stop on the top sheet, allowing it to run over this sheet until the blade is inserted between two sheets, to separate the selected ream above from the remaining pack of sheets below. The edge of the selected ream is then raised and it is pushed towards the packaging machine downstream. In another, similar case, the machine which prepares the packs of sheets from which the reams are obtained counts the sheets and inserts a marker between one sheet and the next to define a ream in accordance with a preset number of sheets; the marker is a piece of paper or similar material, usually coloured, which protrudes from the pack of sheets.
The operator must, therefore, lift and push the ream selected (again with the afore-mentioned gauge or, alternatively, automatic selection systems), positioned above the marker, in the direction of the packaging machine.
Selection using automatic systems is extremely precise, although the markers are not always in the same position, due both to varying sheet dimensions and the different machines which prepare the packs. In particular, the manual selection of reams from a pack of sheets using a gauge is, given the production rates of current packaging machinery, the considerable size and weight of the reams, inconvenient and difficult for the operator.